C
The decrease in native birds will be due to the increased competition for food. They may adapt to different foods; however, the initial and most prominent effect will be that of the native birds' population declines.
The requirement was established principally to address the growth of LISTERIA MONOCYTOGENES, which is a bacteria that has the capacity to continue growing even at refrigerated temperatures. The date marking procedure was put in place in order to make sure that the affected foods are discarded before the bacteria can initiate food borne illness.
<span>Zookeepers
have a difficulty of keeping koala bears alive because Koala bears are
susceptible to viral infections. There is a virus that is present to Koalas
which is called the Koala retrovirus. Koala retrovirus makes a Koala bear more
susceptible to infections and even cancer. </span>
Natural variation provided the phenotypes that natural selection then acted on, over time causing evolution